Solenoid interrupter



Jan. 13, 1959 J. D. woon soLENoIn INTERRUPTER 3 Sheets-Sheet 1 Filed May 3, 1956 ANVENTOR.

JOSEPH n. woon ATTORNEYS y Jan 13 l959 J; D. woon SOLENOID INTERRUPTER u s 'sheets-sheet 2 Fg'led May 5, 1956 INVENToR. JOSEPH D. WOOD ATTORNEYS Jan. 13, -1959 J. D. wooD SOLENOID INTERRUPTER sheets-sheet s Filed May-5,l 1956 INVEN TOR. JOSEPH D. WOOD v 65am BY@ faz-50, i

United States Patent O SOLENOID IN TERRUPTER Joseph D. `Wood, Wayne, Pa., assigner to I-T-E Circuit Breaker Company, Philadelphia, Pa., a corporation of Pennsylvania Application May 3, 1956, Serial No. 582,415 sclatms. (c1. zoo- 144) My invention relates to an interrupting means for circuit breakers and is more specifically directed to an arc plate construction for circuit breaker interrupting chambers which will force the arc to take the shape of a solenoid.

As is well known in the art yand as may be seen with reference to copending application Serial No. 322,027, filed November 22, 1952, circuit interrupting means effectively interrupt an arc by elongating this arc so as to increase its impedance and by cooling the arc. This elongation has, in the past, been accomplished by many means such as by providing arc plates having tapered slots to squeeze the arc where the slots between adjacent plates are displaced from one another so as to force the arc to travel in a sinusoidal path.

In accordance with my invention, however, the arc is forced to take the shape of a solenoid so as to thereby provide a substantial increase in arc length for a given volume of an interrupting chamber. Furthermore, it is well known that a current traversing a solenoid shape will have a substantially increased inductance which is a very desirable property to be imparted to an arc in an interrupting chamber.

Specifically, I provide an arc plate construction wherein an iron plate is utilized to take the arc away from a moving ycontact drawing out the arc and then conducting the arc current from the iron plate to a pair ofprotruding ears which may be positioned on opposite sides of an insulating plate. These protruding ears are then further constructed to be displaced from one another in the direction of the plane of the insulating plate and the adjacent ears of adjacent insulating plates are similarly positioned to be displaced from oneanother along the plane of the insulating plates.

Hence, once the arc has been transferred from the moving contact through the iron plate and to the prol truding ears, the arc current will travel in the shape of a Isolenoid in view of the displaced construction of the protruding ears with respect to their corresponding inup to the arcing chamber by means of the blow-out coil -or because of its own magnetic field will eventually travel between the tips of the protruding ears. Hence the arc current will perform a -U-type motion in travelling from the protruding ears on opposite sides of an insulating plate and will then form another type of U-shaped motion in travelling to the protruding ear of an adjacent insulating plate so as to complete a full turn ofa solenoid which is formed in travelling throughout the plurality of arcing plates in the arcing chamber.

l have found that there are many variationsof my novel invention that my be utilized. By way of example, the iron plate which receives the arc from the separating contacts may be directly fastened to the iron protruding ears or, if desired, may be positioned in spaced relationship with the iron protruding ears so that a subsequent arc will transfer the arc current from the iron plate to its associated protruding ears.

2,868,927 Patented Jan. 13, i959 ICC Furthermore I have found that I can appreciably increase the inductance of thesolenoid shaped arc by embedding a ferromagnetic material within the insulating plate and isolated from the iron protruding ears and plate.

Accordingly, a primary object of my invention is to provide arcing plates for an interrupting chamber which will force the arc to take a solenoid shape.

Another object of my invention is to force an arc to take a solenoid shape by providing an iron plate for taking the arc from a pair of separating contacts and transferring this arc to a pair of protruding ears which straddle an insulating plate, these ears being so constructed as to force the arc in moving from plate to plate to perform a solenoid type of motion.

A further object of my invention is to provide arc plates for an arcing chamber which force the arc to move in a solenoid type of motion wherein insulating members interposed within the solenoid motion carry ferromagnetic material therein which is insulated from the arc and operate to increase the inductance of the arc.

A still further object of my invention is to provide an arc plate for an interrupting chamber which forces the arc to travel in a solenoid type of motion wherein an iron plate utilized to take the arc from the disengaging contacts has a slot therein through which the movable contact may pass in its lmotion to a disengaged position.

These and other objects of my invention will become apparent from the following description when taken in connection with the drawings, in which:

Figure 1 shows a partial View of a circuit breaker adapted with the interrupted means of my novel invention.

Figure 2 specifically shows the arcing plate of my novel invention and the manner in which they impart a solenoid shape to an arc current.

Figure 3a shows an exploded perspective view of the arc plate of Figure 2.

Figure 3b shows a side view of the arc plate of Figure 3a.

Figure 3c shows a front view of the arc plate of Figure 3a.

Figure 4a shows an exploded perspective view of an arc plate similar to that of Figure 3a wherein the insulating portion has a plate of ferromagnetic material embedded therein.

Figure 4b shows a side view of Figure 4a.

Figure 4c shows a front view of Figure 4a.

Figure 5a shows still another embodiment of my invention wherein the arc plate and protruding ears are connected to one another by means of the arc.

Figure 5b shows a side view of Figure 5a for a plurality of arc plates.

Figure 6a shows a still further embodiment of my invention.

` Figure 6b shows a side view of Figure 6a.

Figure 6c shows a top view of Figurea.

Referring now to Figure 1, it is seen that a circuit breaker seen generally at 20 is comprised of a first terminal Z1 and a second terminal 22 which are bridgeably connected by the contact arm 23. Contact arm 23 which has an operating assembly 24, the details of which may be more fully seen in conjunction with copending application Serial No. 545,956, has a movable contact 25 which is movable into and out of engagement with the stationary contact 26 of terminal 21. When the contact 25 of the contact arm 23 is moved to the disengaged position as seen in the dotted lines of Figure l, the movable contact 25 will disengage and then the arcing contact 27 will subsequently disengage so as to draw an arc between the arcing contact 27 and its cooperating Contact 28 attached to terminal 21.

This arc, when formed, is then transferred from the arcing contact 28 to the arc runner 29 and the arcing horn 30 of the movable contact structure connected to the arm 23. The arc is then elongated as the movable contact arm 23 is moved to its'disengaged position and, if desired, blow-out means such as that described in copending application Serial No. 545,956, filed Nof vember 9, l955, could be utilized to drive the arc into the arc chamber which is generally seen at 31. As the arc is drawn out as seen in conjunction with Figure l and more specifically in Figure 2, the arc comes into contact with the iron plates 32, 33, 34 and 35' since the arc horn 30 moves through slots 36, 37, 33 and 39 of the plates 32 through 35.

It is these arcing plates to which my novel invention is directed and as will be seen hereinafter, their construction is such as to force the arc to follow a solenoid shape. The construction of the arc plates of Figures l and 2 may be more specifically seen in conjunction with Figures 3a, 3b and 3c where it is seen that the iron plate 32 is provided with a first and second protruding ear 40 and 41 respectively, which are positioned on opposite sides of the insulating plate 42.

As then seen in Figure 3b, the insulating plate 42 abuts the iron plate 32 and as then seen in Figure 3c, the ears 40 and 41 are positioned to be displaced'from one another in a direction along the insulating plate 42.

Clearly the construction associated with each of plates 33, 34, and 35 of Figure 2 proceeds in an -identical manner as that of plate 32 as described in conjunction with Figures 3a, 3b and 3c.

Referring now to Figure 2, it is seen that upon disengagement of the contacts of Figure l and the appearance of an arc thereacross, that this arc will be transferred to iron plates 32 through 35 and then to the tips of the protruding ears such as 40 and 41 in View of the tendency of the arc to rise in the arc chamber. The path of the arc is then seen in Figure 2 as going from protruding ear 40 of plate 32 to the protruding ear 43 of plate 37 which is positioned to be displaced from ear 40 along the direction of the plane of the insulating plate 42.

Hence the arc will perform a U-type motion in going from ear 40 of plate 32 to ear 43 of plate 33. The arc will then travel from ear 43 through the material of plate 33 and around the insulating plate 44 of the ear 45 to thereby perform still another U-type motion which will complete a single turn of the solenoid.l

In a like manner, it is then seen that the arc proceeds from the ear 45 of plate 33 to ear 46 of plate 34, ear 47 of plate 34, ear 48 of plate 35, and so on.

As another Vfeature of my novel inventio-n, I have found that I can substantially increase the inductance of the solenoid described above in conjunction with Figure 2 by embedding ferromagnetic material within the insulating plate as may be seen in conjunction with Figures 4a, 4b and 4c.

More specifically, Figures 4a through 4c show the plate 32 of Figures 2 and 3athroughf3c wherein the insulating plate 42 has been adapted to have a plate 49 of ferromagnetic material embedded therein.' Hence by envisaging the structure of Figures 4a through 4c in conjunction with the structure of Figure 2, it may be seen that ferromagnetic material will be positioned inten nally of the solenoid to thereby increase its inductance. Similarly, by embedding the ferromagnetic material 49 within the insulating plate 42, the solenoid shape will not be short-circuited.

A still further embodiment of my invention may be seen in conjunction with Figures a and 5b in which it is seen that an iron plate 5t] having a slot 51 therein for receiving the travel of a movable contact is electrically isolated from the protruding ears such as ears 52 and S3 of insulating plate 54 and ears 5S and S6 of insulating plate 57. ln a like manner, the iron plate 58 is insulated from ears and 56 of insulating plate 57 and ears 59 and 60 of insulating plate 61.

However, the protruding ears which may be of iron for each of the insulating plates are connected together as may be seen in Figure 5b in which the connecting means 62 both connects and fastens ears 52 and 53 of insulating plate 54 while connecting means 63 and 64 serve the same function for their corresponding protruding ears 55, 56, and 59, 60 respectively.

The embodiment of Figures 5a and 5b, however, will operate in substantially the same manner as did the embodiment described in conjunction with Figures 2 and 3a through 3c with the exception of the iron plates 50 and 58 being connected to their corresponding protruding ears through a small arc.

If desired, the insulating plates 54, 57 and 61 of Figure 5b could be constructed so as to have ferromagnetic material embedded therein as has been described in conjunction with Figures 4a through 4c.

It is to be noted at this point that while the irony plates have been described as having a slot therein, that: this slot need not be utilized and that the arc could be: transferred from the disengaging contacts to the iron=v plate by any other desired means. Similarly, the arc'V plates need not be positioned perpendicular to the arc' as has been described herein, but, if desired, could; have been positioned parallel to the arc with the designi of the protruding ears slightly altered so as to obtainl the desired solenoid shape for the arc current.

A still further embodiment of my novel invention isI now seen in conjunction with Figures 6a through 6c.. In vthis embodiment, it is seen that the iron plate 65I having an elongated slo-t 65a therein connected to the protruding ears 66 and 67 by means of the metal fas-v tening means 68 and the insulating spacers 69 and 70 are positioned so as to force the arc to travel in the desired solenoidal shape. Here again, it is seen more speciticially in Figure 6c that the protruding ears 66l and 67 are positioned in a displaced relationship along: the plane of the insulators 69 and 70 which could be` of a glass mica material so as to cooperate with these: insulators in providing the solenoid arc current.

Although I have here described preferred embodiments of my invention, many modifications and variations will now be apparent to those skilled in the art. I prefer, therefore, to be limited, not by the specific disclosure herein, but only by the appended claims.

I claim:

1. An interrupting chamber adapted to interrupt an arc drawn between a pair of disengaging contacts; said interrupting chamber comprising a plurality of spaced iron plates, a corresponding plurality of spaced insulating plates, and a corresponding plurality of pairs of protruding ears; each of said pair of protruding ears extends through'one of said corresponding insulating plates to be electrically connected to one another and to be positioned on opposite sides of said corresponding insulating plate and in spaced relationship with one another along the plane of said insulating plate; said iron plates being positioned in substantially parallel plane relationship with said insulating plates and in arcing relationship with one of said protruding ears of each insulating plate adjacent to said iron plate; said iron plates being further positioned to transfer arcs between said contacts to said protruding ears to impart a solenoid shape to said arcs.

2. An interrupting chamber adapted to interrupt an arc drawn between a pair of disengaging contacts; said interrupting chamber comprising a plurality of spaced iron plates; a corresponding plurality of spaced insulating plates and a corresponding plurality of pairs of protruding ears; each of said pair of protruding ears extends through one of said corresponding insulating plates to be electrically connected to one another and to be positioned on opposite sides of said corresponding insulating plate and in spaced relationship with one another along the plane of said insulating plate; said iron plates being positioned in substantially parallel plane relationship with said insulating plates and in arcing relationship with one of said protruding ears of each insulating plate adjacent sur iron plate; the adiacent protruding ears or" adjacent insulating plates` being displaced from one another along the plane of said insulating plates; said iron plates being further positioned to transfer arcs between said contacts to said protruding ears to impart a solenoid shape to said arcs.

3. An interrupting chamber adapted to interupt an arc drawn between a pair of disengaging contacts; said interruptingl chamber comprising a plurality of iron plates each having pair of protruding members, an insulating plate for each of said iron plates; said iron plates being positioned to have an arc between said pair of disengaging contacts transferred thereto; each of said iron plates eX- tending into its corresponding insulating plates and having its protruding member extending through said last mentioned insulating plates; said iron plates being `further adapted to transfer said arc to said pairs of protruding members; each of said pairs of protruding members being positioned on either `side of one of said insulating plates and being spaced from one another along the plane of said insulating member; adjacent protruding members of adjacent insulating plates being displaced from one another along the plane of said insulating members; said arc being driven in a solenoid type of motion when traveling along successive protruding members.

References Cited in the iile of this patent UNlTED STATES PATENTS 2,227,134 Hara Dec. 3l, i940 2,293,487 Eartlett Aug. i8, 11942 2,575,730 Sandin etal Nov. 2G, 1951 2,584,570 Frin Feb. 5, 1952 2,654,012 Cellerini Sept. 29, 1953 2,668,890 Latour Feb. 9, 1954 2,707,739 Latour May 3, i955 FOREIGN PATENTS 547,549 Germany Mar. 26, i932 439,025 Great Britain Aug. 26, 1941 UNITED STATES PATENT oEEICE CERTIFICATION OF CORRECTION Patent No. 2,868,927 January 13, 1959 Joseph D. Wood 1t is hereby certified that error appears in the above numbered patent requiring Correction and that the said Letters Patent should read as corrected below'.

Column line 21, list of references. cited, under "FOREIGN PATENTS", for the patent number "439,025" read 539,025

Signed and sealed this 11th day of July 1961.

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD y Attesting Officer Commissioner of Patents UNITED STATES PATENT oEEICE CERTIFICATION OF CORRECTION Patent, No. n2,868,927 January I3, l959 Joseph D. Wood It is hereby certified that error' appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below'.

Column line 2l, list of references. citedl under "FOREIGN PATENTS" ,A for the patent number "439,025" read 539,025

Signed and sealed this llth day of July l96l.

SEAL) Hest! ERNEST W. SWIDER DAVID L. LADD `Ath-:sting Officer Commissione1-` of Patents 

